To Hyphenate or Not to Hyphenate: That is the Question

Another confusing proofreading issue is hyphenated words. This is particularly true when the words are sometimes hyphenated and sometimes not depending on how the word is used. There are, of course, rules regarding hyphenation.

• Always hyphenate ex, elect, and designate when attaching them to titles. For example "Ex-President Carter."

• You can also use "then" before a title to indicate that the person was acting in that capacity at the time you are describing. Used in this way, it will be hyphenated when it would be confusing otherwise.
• Then Governor Mecham was impeached in Arizona. This could be read to mean that Governor Mecham's impeachment happened next.
• Then-Governor Mecham was impeached in Arizona. This would be read to mean that Governor Mecham was acting governor at the time he was impeached.

• Family titles starting with grand (such as grandmother) are written without a hyphen; however, family titles starting with great (like great-grandmother) are written WITH a hyphen for each great (for instance her great-great-grandmother).

• When used as nouns, terms such as African Americans or French Canadians are not hyphenated. When they are used as adjectives such as African-American politicians or French-Canadian residents, they would be hyphenated.

• Fractions written out would be hyphenated, such as one-third and three-fifths.

• Compound numbers such as thirty-five and six hundred eighty-four should be hyphenated.

• An age that modifies a noun is hyphenated.
• My 40-year-old neighbor has three barking dogs.

• An age that is an adjective phrase that comes after the noun is not hyphenated
• My granddaughter will be 13 years old soon.
• The twins are two years old.

The biggest hyphenation issue that I see consistently is third party. Hyphenating third party depends on how it is used. 

•  When third party is used as a modifier, it should be hyphenated.
• The bill for the third-party vendor was past due.
• It would NOT be hyphenated when not used as a modifier.
• The bill was sent to the third party for payment directly to the vendor.

For an easy test to see if the phrase is a modifier that requires a hyphen, try each word alone with the noun. If it doesn't make sense, you need a hyphen. If it DOES make sense, then you do not use a hyphen:

• In the example above, third vendor does not make sense so third-party vendor should be hyphenated.
• She prefers high-quality clothing. High clothing does not make sense so high-quality should be hyphenated.